<a href="?op=toaddcategory" class="btn">Categories</a> 
<a href="?op=add" class="btn">Add Product</a> 
<a href="?op=link" class="btn">Links</a> 
<a href="?op=images" class="btn">Images</a> 
<a href="?op=comments" class="btn">Comments</a> 
